Combustion knock is an undesirable phenomena which occurs in internal combustion engines. During the compression cycle in an engine cylinder, a spark from a spark plug ignites a portion of a compressed air/fuel mixture in the cylinder. As the spark-ignited portion of the mixture burns, the remainder of the mixture is heated above its self-ignition temperature.
Time-consuming chemical reactions in the fuel delay the self-ignition of the remainder of the mixture. During normal combustion, the spark ignited portion of the mixture burns rapidly enough to consume the remainder of the mixture before the chemical reactions can be completed.
Combustion knock takes place when the remainder of the mixture self-ignites before the spark-ignited portion of the mixture can burn that remainder. The self-ignition causes undesirable noise and overheating in the engine cylinder and often causes mechanical damage to engine parts, such as the pistons and spark plugs.
The problem of combustion knock is particularly common during warm weather. The warmer weather raises the temperature of the engine and thus of the unburned mixture. As a result, the chemical reactions in the remainder of the mixture are often initiated more quickly, allowing the unburned mixture to self-ignite before being consumed by the spark-ignited portion of the mixture.
To combat the problem of combustion knock, mechanics and manufacturers often recommend the use of higher octane fuels. Chemical reactions in higher octane fuels take longer to complete before self-ignition than in lower octane fuels. The longer delay in completing the reactions provides the spark-ignited portion of the mixture more time to burn the remainder of the mixture before self-ignition can occur. Unfortunately, the delay often is not long enough to prevent combustion knock from taking place. Additionally, the use of higher octane fuels increases the operating costs of the internal combustion engine.
Accordingly, a general object of the invention is to provide a kit and a method to improve the operation of an internal combustion engine.
Another object of the invention is to provide a kit and a method to minimize or eliminate combustion knock.
A further object of the invention is to provide a kit and a method to improve the fuel economy of an internal combustion engine.
Other objects and advantages will become apparent from the following description of the invention.